Before he gets his own game like the ideas we gave he needs to first:
1. First, he must get some E-shop games. 3 or so. Waluigi Pinball and Waluigi Casino, or something like that.
2. Now when he gets more fame, he appears in a WarioWare game. A main role, not cameo.
3. He makes more cameos in Nintendo games... (or playable)
4. BOOM! His game gets announced.

I don't get why Nintendo isn't interested in Waluigi as the character itself looks very interesting with his tennis skills and intelligence. I was hoping that eventually he will star in his own game just like Wario, Toad, Luigi heck even Princess Peach and Yoshi as well!

For the longest time I've been envisioning a Waluigi Pinball game developed by Zen Studios where the story is that Waluigi wakes up in the plumber man-cave and finds that Mario, Luigi, and Wario have all gone off to star in their own adventures so Waluigi just decides to stay home and pass the time with their custom-made pinball machine.

"Good. Everyone's together. Pyrrhon loves a party."
"...It's funny because marriage is terrible!"
If you know the origin of both of those quotes, then you're awesome!
Songs are like hugs that mouths give to ears.
Dreams are easy to achieve if hope is all I'm hoping to be.

Frankly, I don't think it's a good idea to give Waluigi a game out of nowhere.

Nintendo should make New Super Mario Allstars and get Wario, Waluigi, and Daisy next to Mario, Luigi, Peach, Toad, and Rosalina. The game should offer levels that can be done with any character, but only one or two characters would actually make them easy.
That way, every character would have some strong points - Wario can throw coins and/or gets double coins, Waluigi has better throw abilities and firing range for powerups, and Daisy has a glide where she slowly descends when holding the jump button.

Once Waluigi is established for a platformer, Nintendo should give the Waa his own game - I'm thinking of a mix between Wario Land 4 (level and combat design), Kirby's Cave Offensive (multiple paths and collectibles EVERYWHERE), and Earthworm Jim (wacky humour ranging from silly to sick). And the name of that game shall be: Waluigi: Wild Time!

Establish him as a character eh?... Oh! I got it put him in Super Mario 64 3DS(a game that also needs to be made) that way I can stop looking for him in the DS version... seriously I know I wasn't the only one who did this though

Majora's Mask 3D is coming and you know what that means? The Razor Sword is gonna return! ... and still be useless, eh whatever its gonna be in 3D.

I don't think he should have his own game, but I think he should have a major role in a game that's not a spin-off. I have the same opinion for Daisy.

I was thinking he could be in a WarioWare game as Wario's secondhand man who is always trying to one-up Wario. Or maybe in a sequel or spiritual successor to Wario World (a girl can dream!), he can be his partner and help him or have an option to co-op with him. Basically, Waluigi could be to Wario what Luigi is to Mario.

I've always wanted to see Waluigi and Daisy have a major role in a main game, so I'm hoping that it'll happen not too far into the future. I actually see a lot of potential in those two.